MariaDB Business Source License (BSL)

Frequently Asked Questions

This FAQ addresses questions for MariaDB customers and users interested in why MariaDB Corporation is employing the Business Source License (BSL). Vendors and developers interested in learning how to adopt the BSL for their own products should go to

Q: What is Business Source License (BSL)?

A: BSL is a new alternative to Closed Source or Open Core licensing models. Under BSL, the source code is always freely available and it is guaranteed to become Open Source at a certain point in time (i.e., the Change Date). Usage below a specific level in the BSL is always completely free. Usage above a specified level (power users) requires a vendor license until the Change Date, at which point all usage becomes free.

Q: Which version of the BSL does MariaDB Corporation use?

A: BSL 1.1. For MariaDB MaxScale 2.0.0 until 2.0.4, BSL 1.0 was used.

Q: Do the terms and conditions for MariaDB customers change materially between BSL 1.0 and 1.1?

A: No. The changes introduced in BSL 1.1 are wording changes aimed at simplifying the adoption of BSL by other vendors, through setting consistent user expectations on BSL.

Q: Why did MariaDB Corporation adopt a new license for MariaDB MaxScale?

A: MariaDB Corporation adopted BSL to ensure that Open Source development can continue to deliver the innovation benefits of entirely open code (vs. say Open Core), while providing a model for the company to have a sustainable business.

BSL is a licensing innovation designed to drive stronger community participation by making the code freely available and open for any usage, modification or distribution that is below the specified use limitation.

Q: Which MariaDB Corporation products will be under the BSL?

A: MariaDB MaxScale 2.0 will be under the BSL. MariaDB Server will continue to be licensed under GPL in perpetuity, while its connectors will continue to be under the LGPL.

Q: How is the BSL different from Open Core?

A: Open Core offers components where the non-core code is not open, or available in source form, cannot be modified and compiled, cannot be contributed to, and will never be Open Source. By using Open Core software, like with closed source code, you are locked to one vendor. With BSL, as compared to Open Core, the source code is available from the start, can be modified and compiled, contributions are encouraged, the product will become fully Open Source after a period of time and remains free for usage that is under the usage limitations. The importance of the eventual Open Source is that users are free from vendor lock-in. If the vendor decides to stop contributing to the code, users have open access and can modify, update and extend as needed.

Q: How is the BSL different from dual GPL/commercial licensing?

A: When using dual licensing with GPL, companies must pay for a commercial license to use the software with their closed source code. With BSL, the companies are only paying for the software if they want to use the software above the free usage limits. From a vendor perspective, GPL dual licensing only works for infrastructure products that other companies want to deeply embed in their product. BSL works for any kind of software product.

Q: How is BSL different from the Fair Source License (

A: The Fair Source License uses the number of users as a limitation, which makes sense for some types of software such as stand-alone applications, but not for all. BSL limitations are more general and can vary from project to project, depending on what makes sense for a balance between free usage and paid usage. In addition, BSL code is guaranteed to become free Open Source software after a certain specified time.

Q: Can I use the BSL for my own software?

A: Yes, if you own the copyright to your code (or it is based on software with a permissive license, such as BSD). The BSL framework is designed to make it trivial for anyone to release their software under BSL. To convert your software to BSL, you have to add the BSL header to all your software files and include the BSL license file in your software distribution. In addition, you have to add the usage limits and Change Date that suits your software in the header of the BSL license file.

To read more about using BSL for your own products, or modifying existing BSL products, please refer to the Adopting and Developing BSL Software FAQ here.

If you have additional questions about BSL or how it applies to MariaDB Corporation products, please contact us here.